Telegraphic transmitter.



G. A. CARDWELL.

.TELEGRAPHIC TRANSMITTER.

APPLICATION FILED JAN. 15, 1908.

Patented Man 28, 1911.

5 SHEETS-SHEET 1.

la 09 P WITNESSES: 5 Y INVENTOR 1 v 1 Y 1% Y @7655?! 1 9 v g I BY' WL 61421221 fl ATTORNEY G. A. GARDWBLL. TELEGBAPHIG TRANSMITTER; AVPPLIJJATIOH FILED JAN. 15, 1908.

Patented Mar. 28, 1911.

5 SHEETS-SHEET 2.

INVEINTOR WEN ESSES v v waim /AA- ATTORNEYI G. A. CARDWELL. TELEGBAPBIG TRANSMITTER.

urmunron rninn an. 1;, 190a.

Patented Mar. 28, 1911.

5 SHEETS-SHEET 3.

. INVENTOR r/r ATTORNEYJ- G. A. CARDWELL.

TELBGBAPHIO TRANSMITTER.

APPLIUATIOH rILnn IA]. 15, 1908'.

- I Patented Mar. 28, 1911.

5 SHEETS-SHEET 4.

G. A. GARDWELL.

TELEGBAPHIG TRANSMITTER.

APPLICATION rum) um. 15, 1908.

Patented Mar. 28, 1911.

X mo- WITNESSES:

BY 4 D/A/J ATTORNEYJ.

UNITED STATES PATENT OFFICE.

G 'EORGE A. (MlIlEtDW'fELL, OF NEW YORK, N. Y., ASSIGNOR T0 AMERICAN TELEGRAPH I TYPEWRITER COMPANY, OF YORK, N. Y., A CORPORATION OF DELAWAQE.

TELEGRAPHIC' TRANSMITTER.

December 1, 1908, I have described a telegraph typewriter comprising a type wheel 1 the position of which is controlled by a series of electromagnets which are energized in apredetermined sequence for a given let: ter or other symbol. These magnets are included in circuits which afe closed through polarized relays in the" line circuit and-reisponsive to currents of diiierentstrength or which polarity, a given sequence of at least three impulses being required to determine the printing positlon of any letter. The presentinvention forming part of the system relates to the mechanism for transmitting the impulses to effect the closing of the circuits at the receiving station, and, generally statcd, comprises a keylooard selective mech- Ynnism which determines the character ofthe impulses; a commutator for transmitting the impulses in a predetermined sequence; and

mechanism to prevent interference of the impulses. y

*The' invention will be understood by reference tov the accompanying drawings in Figurelis atop viewof the transmitter; 2 atop view of the locking solenoid Y vand 'co'mnmtatorl mechanism; Rig. 3 a vertical longitudinal section on the plane ofthe line '33 of-F-ig. 2';

n Fig. 4atransverse vertical section on the plane of the line H of Fig. 1; Fig. 5 a-longitud'inalvertical "section of the selective mechanism on the planeof the line 5-5 of Fig. 1; Fig. 6 a

' vertical section on the plane of the line 6-6 of Fig. 2; Fig.7 a longitudinal section of the-commutator; Fig. 14 a side view of a.

universal bar in the selective mechanism;

Figs, 8' to 13 both inclusive side rie'ws of the selectorbars; Fig. 15 is a table containmg'the code or=syste1n of the order of the impulses for the characters on the keyboard;- and Fig. 16 1s a general dlagra-mmatic View .of the circuits.

Spe'cificationof Letters Patent.

Application filed January 15, 1908.

Serial No. 410,878.

Similar reference numerals indicate similar part-s 1n the several views.

'teferring more particularly to Fig. 16,

L and L designate the two line wires from the transmitter to the distant or rece vlng station. Atthe latter are polarized relays Patented Mar. 28, 1911.

ceiving station propersequence a predetermined code or system of sending in the impulses is essential. In the present .sys tem the code adopted bv'me is given in Fi 15, the numerals in said code reading verticallydownward indicating the sequence of the impulses through the relay contacts '1 2,8 and 4. That is, for example, for the letter T the first impulse will be through contact 2, the second impulse through contact 4, and the third impulse through contact 1. It will be noted from this table that the sec ond' impulse must come through a different contact from that of the first impulse, and

that the third impulse must come through a different contact from that of the secondand immediately preceding impulse, but may or may not be through the same as the first impulse in the series. In other words, the first impulse may come through any one of the four relay contacts; the second im pulse through any one of the contactsex- I cept that through which the first contacts except that through which the second impulse came. WYhen a given one of the contacts 1, '2, 3 or 4; is closed a circuit will be closed at the receiving station for the purpose of positioning. tie type wheel and to effect the printing of the characters struck on the keyboard at the transmitting station and for effecting otheroperations as fully set forth in my said patent.

The line circuits L and L are connected respectively to brushes 5 and 6 of a commutator 7 the latter comprising three indev impulse came; and the third through any one of the pendent sect-ions, one for local purposes, as hereafter described, and the others for transmitting the nn'pulses 1n the selected order.

The construction of the commutator is shown a continuous ring 15 of conductive material on which aremounted three segments 16, 17

and 18. .The brushes 5 and6 are in constant electrical engagementwith the rings 8 and 15 respectively and it willbe readily under stood that an impulse, whether negative or positive, through any one of the segments 9, 10 or 11 will be transmitted through ring 8 to line L, and that an impulse, whether negative or positive, through any one of the segments 16, 17. or 18 will be transmitted through ring 15 to line L These commutator segments are insulated from theshaft as shown in Fig. 7.

Current for operating the rela s is supplied by batteries N and I, the iormer bemg grounded at its positive side and the latter at its negative side. Battery N-is connected with the commutator brushes 12, 13 and let throughcircuits 22, 23 and 24, which circuits include the contacts 22, 23 and 2 1 respectively. Battery P is connected with the same commutatorbrushes through circuits 25, 26and 27, which .circuits include the contacts 25, 26 and 27 respectively. Battery N is connected with thecommutator brushes 19, 20 and 21 through circuits 28,

29 and 30, which circuits include the contacts28, 29 and 30 respectively; and bat tery P is connected with the same brushes through circuits 31, 32 and 33, which circuits include contacts 31, 32 and 33 respectively. It: will be seen from this that in order to senda negative impulse over line Lt one of the three contacts 22, 23 or 24 must be closed; to send a positive'impulse over line L one of the three contacts 25,- 26 or 27 must be closed; to send a negative impulse over line L one of the three contacts 28 29 and 30' must be closed; and to send a positive impulse over line L one of the three contacts 31, 32 and 30 must be closed. The

commutator 7 is arranged soas to be rotated in a left-handed direction as viewedin' Fig. 10, and the segments 9, l0 and IIa-re so arranged that the projections thereon are in step-like formation so that the'segirient 9 will first make contact with the corresponding brush 12 followed by contact of segment 10 with its brush 13 and segment llwitli its brush 14. The same, arrangement oft-he 30 giving a negative impulse.

segments 16, 17 and 18 is observed, said segments contacting with the corresponding brushes 1%), 20 and 21 in the order given. As in the present system three impulses at least are required, the first impulse must be sent by closing one of the four contacts 22, 25, 28, or 31, as will be seen by tracing the circuits in which these contacts are 111- cluded that they lead either to the brushes 1.2 or 19. That is, the brush 12 is included in the circuits of the contacts 22 and 25, the former transmitting a negative impulse and the latter a positive impulse; and the brush 19 is included in the circuits of contacts 28 and 31, the former transmitting a negatlve and the latter a positive impulse. VVhatever, therefore, the character of the first impulse, it. must-be transmitted from brush 12 to the corresponding segment 9, or from brush 19' to the corresponding segment 16,

and from thence either to line L or to line L In the same way it will be seen that the second. impulse must be transmitted through either segment 10 or segment 17 for the reason that the brush 13 of the former is included in the circuits which include contacts 23 and 26, and that brush 20 is in cluded in the' 'circuits which include the contacts 29 and 32", so that the second impulse must come through the closing of one of the four contacts 23, 26, 29 or 32.

seen that the third impulse must come In the] same manner by tracing the circuits 1t 1s through the closing of one of the four conf tacts 2a, 27, 30, or 33, 7

Comparing the arrangement of the contacts 22 to 33 both inclusive with the code given in- Fig. 15 it will be seen that the latter indicates not only the sequence of the impulses through the relay contacts 1, 2, 3 or 4, but also the character of the impulses.

Thus for the letter D the code indicates that.

impulse; the second impulse must close relay contact t which is in line L and requires that the circuit shall be closed through segment'17, brush 20 and contact 32 giving a positive impulse. The third impulse re quires the closing of relay contact 3 which is in line L requiring the circuit to be closed. through segmentlS, brush 21 and contact In the same manner the circuits of the successive impulses for any, other letter on the keyboard or any operation such as line spacing, carriage return, eta, inay be traced.

'Aconven-ient manner of regarding the contacts 22 to 33 is to consider them as divided into four groups of threeeach, the first comprising contacts 22, 2'3" and 2 1 adapted when any one of them is closed to send 'anegative impulse over lineL" through the commutator segments 9, 10 and 11 respecively to close relay contact 1 accord ng. as to whether it is the first, second or third contact of the series to be closed. The second group comprises contacts 25, 26 and 27 adapted, when any one of them is closed, to send a positive impulse over line L through commutator segments 9, 10 and 11 respectively to close relay contact 2 according as to whether it is the first, second or third contact of the series to be closed. The third group comprises contacts 28, 29 and 30 adapted, when any one of them 1813-1053(1, to send a negative impulse over line L through the commutator segments 16, 17 and 18 respectively toclose relay contact 3 ac-' cording as to whether it is the first, second i or third impulse ofthe series to be closed.

The fourth group comprises contacts 31, 32

and 33 adapted, when any one of them is closed, to send a positive impulse over line L through the commutator segments 16, 17 and 18 respect-ivelyto'close relay contact 4 according as to Whether it is the first, second or third contact .of the series to be closed. Each of the circuits 22-to 33 may be further considered as normally open at two points; that is, at the breaks 22 to 33' inclusive, and at the commutator, sothat the closing of a given break 22 to 33 and the rotation of the armature in a left-handed direction Will completely close a given circuit to transmit a characteristic kind of impulse either over line L or L As, for example, to effeet the printing of letter J the relay con-' tacts must be closed in the order 4 1-3. As relay contact 4 is closed by a positive impulse over line If, it is required that circuit 31 shall be closed through contact 31, brush l9 and commutator segment 16. As

relay contact 1, the second of the series to be closed, is closed by a negative impulse over line L it. isrequired that circuit 23 shall be closed through contact 23, brush 13 and commutator segmentll). As relay contact 3, the third of the series to be closed, is .closed by a negative impulse over line L it is required that circuit 30 shall be closed throughcontact 30, brush 21 and commutator segment 18. The complete circuits for the transmitting of the required impulses for'any other letteror' operation may be readily traced by taking the sequence of impulses from Fig. 15.

Instead of grouping the'contacts 22 to 33 as above described, they may be considered asdivided into three groups of four each asfollows. The'first group comprises 22, 25, 28' and 31, the closing of any one of which will send the first impulse of the serles; the second group comprises contacts 23, 26, 29 and 32, the closing of any one of which will send the second impulse of the series; and the third group comprises.-

contacts 24, 27, 30 and 33., the closing of any one of which will send the third impulse of the series, it. being understood, of course,

that the rotation of the commutator is necessary to send the impulses.

Having described .the several circuitswhich are closed through the commutator and the contacts 22 to 33, I will now describe the mechanism forclosing said con' tacts. Referring to Figs, 1, 3 and 4, the numeral 34 designates the casing in which the operative parts are assembled; The keyboard contains thirty-two keys, or thirty.-

three keys including the space bar 35, of' which twenty-eight are for printed, characters and the remainder for figures, carriage return, etc. The keyboard shown 1s of the universal type and 1t is to be understood that any number of keys may be employed. r

The key levers 36 are pivotally mounted on a rod 37 secured to the casing and are pressed upward in normal position by springs 38 against a plate 34 forming part of the casing. the key levers is a series of notched'bars, seven in number and designated respectively 39, 40, 41, 42, 43, 44 and..45, whichare illustrated in detail-in Figs. 8 to 14 inclusive...

Extending transversely of These bars are slidably mounted in openings in the side wallsof the casing and rest upon rollers 46 mounted in brackets as shown in Fig. 5, and are provided .on the lower edge with notches 47 intowhich project spring arms 47 to hold the barsinnormal position,

said springs bearing against stops 47 sc cured to the casing. The ends of the bars 39 to 45 project beyond the side walls of the casing and are covered with a cap of insulating materiali The contacts 22, to 33, as shown in Figs. 1, 3 and 5, are mounted on blocks: of insulating material secured to the casing and are placed in juxtaposition with the bars 39 to 44 inclusive so that when a given one of said bars is moved to the right or left one of the twelve contacts will be closed. The desired movement of the selector bars is effected by the key levers when the latter are depressed, and for-that purpose the bars are mounted transversely to the key levers and immediately below the latter so that the depression of a key lever in the ordinary manner will engage the bars.

It being necessary to send three impulses to the distant station, at least three of the twelve contacts 22 to 33 must be closed, and to efi ect this three of the bars 39 to 44 must be moved. The said bars are, therefore, laid out, as shown in Figs. 8 to 13, with a certainnumber of vertical and inclined cuts or notches, the latter being inc-lined upward to the left to'eliect a movement of the bar to the left, and inclined upward to the right to effect a movement of the bar to the right. These bars are so cut and'arranged that the bars39, 40 and 41 ,when moved to the left will close the contacts 22', 23' and 24' to send a negative impulse, over line L, and when moved to. the right will close. contacts 25, 26 and 27 to send a positive impulse over line L; and the bars 42, 43 and 44 when moved to the left will close contacts 28, 29' and 30 to send anegat-ive impulse ovcr line L and whenmovedto the right will close contacts 31', 32 and 33' to send a positive impulse over line L The notches are so disposed, however, that when a given key lever is depressed but three of the six bars'will be moved; that is,-when a bar is to remain Stationary it is cut with a vertical notch into. which the key lever passes witho'utfimparting any movement tosaid bar;

but when the key lever strikes against the wall of one of the inclined notches the bar will be moved to either the right or the left as above explained. The bars that will be moved for any given letter may be readily found by laying a straightedge across the bars 8 to 13'. As, for example, when the key leverof the letter J is depressed it will pass into a vertical notch in, the bars 39, 41 and 43 and said bars will, therefore, remain stationary, but will strike againstthe inclined walls of notch, 40 in b r 40, and 44 in bar 44, moving both of said are to the left and closing contacts 23" and 30 respectively. It -wil l:also strike against the inclined wall of notch 42 of bar 42, moving the latter to the right and closing contact 31. For the letter it will be seen that, the key leve'r will pass into vertical notches inthe bars 40, 42 and 44, said bars, therefore, remaining stationary. Bar 39 will be movedto the left closingcoutact 22, and bars 41 and43 will be'moved to the right closing contacts 27' and 32 respectively. For the letter E the bar's and 41 will be moved to the right closing contacts 25 and 27 respectively, and bar 40. will be moved'to the left closing CO11 tact 23. The remaining three bars; namely, '42, 43 and 44, remain stationary. In the same manner the bars moved upon the depression of any of the levers of the keyboard may be readily found.

It heing understood that the three moved simultaneously therefore closing the three selected contacts simultaneously, it is necessary to provide mechanism for sending out the impulses successively and in their proper order. This is effected by disposing the commutator segments 9, 10 and 11 in one section, and segments 16, 17 and 18 in the other section, in the step like. formation heretofore described, 'and as illustrated in l ig. 16. The commutator may, therefore, heregarded as a selective mechanism for completely closing the circuits in a predetermined sequence, breaks in which circuits avere closed hythe movements of the selcctor bars. This will he made clear by refeukuce to Fig. 16, taking the same letter J.

bars are When its key lever is depressed the bars and 44 will be moved to the left and 42 will be'moved to the right closing respectively contacts 23, 3 0 and. 31. Bearing in mind the grouping of the contacts, it will be seen that contact 31 is one of the contacts through which the second impulse must come, and that 30' is one of the contacts through which the first impulse must come; that contact 23: is one of the contacts through which the third impulse must come. The impulses must, therefore, be sent through the circuits in which are included the contacts 31, 23 and 30' respectively.

By tracing the circuits it will be seen that, the first impulse will be sent over circuit 31,

through brush 19, commutator segment 16,

-to line L which will close relay contact 4;

the second impulse will be sent over circuit 23, through brush 13, commutator segment 10, to line L closing relay contact 1; and the third impulse will be sent over circuit 30, through brush 21, commutator segment 18, to line L to close rela contact 3. The relay contacts will, there ore, be closed in the order 4-1-3 as required by the table given in Fig. 15.

When the key lever of letter O is depressed contacts 22,-27 and 32 will be closed. The first impulse will, therefore, be sent over circuit 22, brush 12, commutator segment 9, line L to close relay contact 1;

the second impulse will be sent over circuit 82, through brush 20, commutator segment 17, to line L .to close relay contact 4; and

the third impulse will'be sent over circuit 27, through brush 14, commutator segment 11 to line L to close relay contact 2. In a similar manner the sequence of the circuits completely closed at the commutator may be readily traced. As the space bar 35 has two levers, the bars 39 to 45 are similarly notched at both ends.

There remains to be described the mechani'sm for rotating the commutator and for with notches inclined in the same direction;

that is, upwardly to the left. This is a universal bar and is moved to the left whenever any one of the key levers is depressed. The

purpose of said bar is to close a contact 48 included in a circuit49, which circuit also includes a solenoid coil/50 and battery 51. Connected to the core 50 of said solenoid is a lever 52 pivotally mounted on a shaft near its lower end. On the side of. said lever is pivoted a spring-pressed pawl 52 which en-" the teeth of a ratchet wheel 53 fast on the shaft of a gear wheel 54. The latter meshes with a pinion 54 on the commutator shaft 7. Whenever, therefore, a. key lever is depressed the bar 45 will be moved to the left closing contact 48 and thereby energizinc 'selenoidfio, the core of which ,Will be,

drawn inwardly causing the pawl 52 to rotate the i.'at .'he t wheel 53 one tooth thereby rotatingthe commutator. Meshing with a spur gear on the shaft 7 is a pinion 55 on the shaft 56 of a speed regulator or gov-- the plate 57 is so moved that the arm 58' passes through the opening therein and 7 above the plate and acts as a stop against which the plate strikes when the wheel 55 completes one revolution. This brings the commutator to an absolute stop and to pre vent rebound a ratchet wheel 59' is keyed on the commutator shaft which wheel is engaged by a back lash pawl 59'. To provide an absolute stopy-for the "gear wheel fit-I se-h l-ure to the side-lever 52 a pawl 52 which engages the back of one of the ratchet teeth fi lhvlieii the lever 52 is moved forward. X spring 52 restores the parts to normal position when the solenoid 50 is deenergizcd.

'hen contact 48 is closed by the movement of notched bar-4t5 solenoid 50 will be immediately energized and the commutator rotated. may be sent, it is necessary that there shall be a complete rotation of the commutator and this can be secured only by maintaining solenoid 50 energized for a suflicien't length of time. The operator may hold a given key lever depressed to thereby maintain contact 48 closed, but I do not depend upon this. If a key lever isgiven a very light touch, although contact 48 would be closed through the movement of the universal bar'4e5, the return of the key lever to normal position would result in the opening of contact 48 and. solenoid 50 being thus deenergizech the commutator would be given a partial rotation only and thesending of the impulses would be interrupted. In order, therefore, to insure that solenoid 50, after being energized through the closingof contact 48, shall remain energized long enouglrto effect one romplete rotation of the commutator irre- ,spective of whether contact 48 remains clo ed or is opened after the rotation of the commutator has begun, I co'nstructthe commutator with a section comprising a continuous ring 60 similar" to the rings 8 and 15, and two segments 61 and-62 see Figs. 7 and 16), These segments are'in constant electrical engagement with each other-and with the ring 60and are insulated from the com- The ring mutato'r shaft as shown in Fig. 7. 60 is n constant electrical engagement with In order that all of the impulses a brush 60 and'the segments 61 and 62 are adapted, when the commutator is rotated, to engage brushes'Gl" and 62 respectively. In

. the normal positions of the parts the brushes 61' and 62 rest upon an insulated section of the commutator. The segments 61 and 62 are of such length that a very slight movement of the commutator is sufficient to bring them into contact with their respective brushes so that when a'key lever is depressed sufficiently to close contact 48 solenoid 50 will be immediately energized, and the rotation of the commutator will close an auxiliary circuit 49, in which the'brush 62 is included, through solenoid 50 and the latter will remain energized to insure the completion of the rotation of the commutator to send in all of the impulses, regardless of the condition of contact 48. So far, therefore, as the rotation of thevcommutator is concerned it-is not necessary thata given key lever be held depressed after segment 62 has ein contact with its'brush 62',

In order. to prevent any interference of impulses it is essential that when a key lever is depressed it should be locked againstfre turn movement. and all the other key levers should be locked open; that is, any movement of them; prevented, until the impulses necessary for a given letter have been transmitted. T 0 effect this I include brush 61' in a circuit 63 which also includes'a magnet in the form of a solenoid coi1'64, and battery 51," so that when the commutator is rotated circuit 63 will be closed thereby energizing magnet 64-. The core of-solenoid 64: has connected thereto a projecting rod 64: and the latter has pivotally connected theretoa link 65 which is connected to rock shaft 66 (see Figs. 3 and 4t). Rigidly secured to the said rock shaft are a number of upwardly projecting hooked arms or latches 67, therebeing as many arms 67 as there are key'levers. On the side of each key lever .is a pin 68 which, when the key lever is in normal position, lies outside of the path of the corresponding arm 67. lvhem'however, a given key lever is depressed its pin 68 willbe carried below the corresponding arm 67, and

moved to their normal positions until the completionof the rotation of the commutator.

It will be noted that each of the selector bars is notched differently from the others so that no key lever will move thesame com- =bination of bars as is moved by any other lever. The notches are so arranged that each key lever will always move three bars in addition to the universal bar 45, thus closing a combination of three contacts for sections along-the upper edge of each bar between the notches, it being. appar'entthat when the normal relation of the bars is disturbed by depressing a given key l'everQtha-t the notches for any other key lever-will kbe displaced relativel thereto so that any other key lever, i depressed," will strike against the upper edge of the notched bars. In addition, therefore, to the features here tofore explained ,thisone of looking a depressed key leve" psed and all of the other key levers open that is locked against depression, isof impfortance. From the manner of grouping-the contacts 22' to 33,-it is imp'osslble to opposite contacts at the same time. close either one the contacts 22' or 25' but not both at same time. This avoids any possibility; of short circuiting.

Upon the completion of the rotation of the armature the brushes 61 and 62, will rest upon the insulated section of the commutator thereby opening circuit 63 and deenerglzlng magnet 64. A spring 69 (See Fig. 4) secured to the casing and to the link 65 will then be free to act to rock the shaft 66 in a direction the reverse of that when solenoid 64 was energized thereby restoring the arms 67 to normal position, and permitting the spring 38 of the depressed lever to restore the latter to normal position. The three selector bars, now being released. from engagement with a key lever, are restored to normal position, by the spring arms 47 thereby opening the three contacts of the se ries 22 to 33' which were closed when the key lever was depressed. All of the operat1ve parts are now in normalposition and are ready for the transmission of the impulses n'ecessaryto effect the printing of the next letter or other symbol. i

From the foregoing description it will be seen that the present system provides cir cuits which are normally open at at least two points and that a plurality of these circuits are simultaneously closed at one point and selecti ely closed at the other point to r example, bar 39 can.

transmit the impulses in a pro-determined sequence; and that the complete rotation of the commutator by which the impulses are selectively transmitted is always insured regardless of the time that a given key lever remains depressed provided, however, the

key lever is depressed sulficiently to start the rotation of the commutator. gard as one of the essential characteristics of my invention and desire to claim thesame broadly without specific reference to the details of the mechanical construction in-.

volved, it being understood that 'bycomplete rotation of the commutator is meant a suflicient rotation to carry the commutator segments into contact with and past "the corresponding brushes for completely closing the three selected circuits in a predetermined sequence and to position the" commutator properly to transmit the impulses for the next succeeding character of the keyboard. Solenoid magnet 50 is, therefore, introduced as a means to efl'ect the rotation of the commutator thedesired'distance so.

pressedlever'have been transmitted? If the operator should always hold a key lever depressed long enough to keep contact 48 closed to rotate the commutator a suflici ent distance to close circuit 63 through thelocking magnet 64 to thereby lock the given key lever depressed, contact 48 wouldbe held closed and there would be nonecessity to introduce the commutator segment 62 and the auxiliary circuit 49. The latter circuit is of advantage, however, in that should the commutator be accidentally rotated. circuit 63 would be closed through segment 61 and brush 61 thus throwing all of the locking arms. 67 into such position as to prevent the depression of any 'key lever thereby pre venting the closing of contact 48 or any of the contacts 22' to33.-

What I claim and desire-to secure by Letters Patent is I 1. In a transmitter, the combination of a key-board mechanism, a plurality of circuits, notched selector bars actuated directly by the key levers for simultaneously closing, normally open contacts in said circuits in setsof the same number for every letter orasymbol represented on the key-board, means forcom This I re- Cir ' of the same number for every letter or syni bol represented on the key-board, a commutator for completely closing the selected circuits in a predetermined sequence to transmit impulses to a distant station, and means for holding said contacts closed until the impulses have been transmitted.

3. In a transmitter the combination of a keyboard mechanism comprising means for simultaneously closing a break in a plurality of circuits, a commutator for completely closing said circuits selectively to transmit impulses in a predetermined sequence to a' distant station, a magnet and means connect-' ed therewith to rotate said commutator, a normally open circuit 111 which said magnet is included and means for closing the same when a key lever is depressed, and means for closing an auxiliary circuit through said magnet after the rotation of the commutator has begun.

4. In a transmitter the combination of a key-board mechanism comprising means for simultaneously closing a break in a plurality of circuits, a commutator for completely closing said circuits selectively to transmit impulses in a predetermined sequence to a distant station, a magnet and means connected there.- With to rotate said commutator, a circuit in which said magnet is included, means for closing a normally open contact in said circuit when a key lever is depressed, and means for closing an auxiliary circuit through said magnet after the rotation of the commutator has begun and for maintaining'said-auxil iary circuit closed independently of the condition of said normally open contact.

5. In a transmitter, the combination of the key levers, selector bars adapted to be moved by said levers in two directions, circuits havin normally open contacts adapted to be closed by said bars When moved in either direction, and mechanism for completely clos-' ing said circuits to transmit the impulses in ya predetermined sequence to a distant Sta-- tion.

6. In a transmitter the combination oft-he key levers, selector bars extending transversely thereofl'said bars beingcut so as. to

be engaged and moved by said levers and so' disposed that a plurality of said barswill'be moved when a given lever is depressed, circuits having normally open contacts adapt: cd totbe closed by said bars, and selective mechanism for completely closing those circuits a break in which was closed by said J adapted to be closed by said bars, selective mechanism for com ,letely closing those cirthe circuit of said magnet, and means conbars to transmit the impulses in a predetermined sequence to *a distant station,

7. .In a transmitter the combination. of the key levers, selector bars extending transversely thereof, said bars being cut 'so asto be engaged and moved by said levers and so disposed that a pluralitybf said bars will be moved when a given lever is depressed, circuits having normally open contacts cuits a break in w ich was closed by said bars to transmit the impulses iii a predeter mined sequence to a distant station, and means for locking said bars in position to maintain the corresponding contacts closed until all the impulses have been transmitted.

8.0In a transmitter, the combination of a key-board selective mechanism comprising means for closing a plurality of circuits for transmitting electric impulses in a predetermined sequence to a distant station, an

electro-inagnet, means actuated by the keys of the key-board when depressed to close trolled by said magnet to lock the keys in their depressed position. I

'9. In a transmitter, the combination of a key-board selective mechanism comprising means for closing a plurality of circuits for transmitting electric impulses in a predetermined sequence to a distant station, an electro-inag'net, means actuated by the keys of the key-board when depressed to close the circuit of said magnet, and means controlled by said magnet to look a depressed key-lever closed and the other key-levers open until the impulses have been transmitted.

10. Inatransmitter the combination of the key levers, selector bars adapted to be moved by said levers, circuits having normally open contacts adapted tobe closed'by said bars, said circuits being so grouped that a given bar when moved in' one direction will close contact to transmit. a characteristickind the key levers, selector bars adapted to be .moved by said levers iii one direction for certain letters and in the opposite direction for others, circuits having "normally open contacts adapted to be closed by said bars, the depression of any key lever simultaneously moving a plurality of said bars to close a corresponding number otsaid contacts, and means'i'or completely closing said circuits predetermined sequence to 5 transmit impulses to a distantstation.

' 12. In a transmitter tliecombination of the key levers, selector bars adapted to be moved by said levers, said bars having notches adapted to receive the key levers so as to be moved thereby in one direction for certain letters and in an opposite direction for others and so disposed relatively toeach cum-um atleast three of said bars will be moved simultaneously by any one of'sald levers, circuits having normallyopen contacts adapted to be closed/by said bars, and

means for completely closing said circu ts in a predetermined sequencefor transmlt- 10- ting impulses 'to a distant station.

- 13. In a transmitter the Combination of the key levers, selector bars adapted to be moved by said levers, said bars being so disposedrelativ'e'ly to each other thatwhen' a given key lever is depressed the normal-relation is disturbed so as to preventany other key lever being depressed. a 14. In a transmitter the combination of the key levers, selector bars adapted tobe moved by depressing said levers, circuits- .having normally open contacts adapted to beclosed by. 'saidbars, means foreom pletely closing those circuits a break in which was closed by said bars to transmit' impulses in a predetermined sequence to a distant station, and means for locking a given key lever in its depressed position, said bars being so. disposed relatively to each other that whena given keylever isdepresscd their normal relation will .be disturbed so as to prevent anyother key lever being depressed until all the impul'sescorresponding to the depressed lever have been transmitted.

15. A transmitter comprising a plurality of circuits, a commutator having segments and corresponding brushes, said circuits be ing divided into four groups of three each and each commutator brush connected to at least one circuit in two of said groups,

40 means for simultaneously closing a break in one circuit of at least three 'of said groups, whereby impulses of different characteristics may be transmitted through a given com- 'mutator segment to a distant station, and a characteristic kind of impulse may be transmitted through a plurality'of the tr'ans mitter circuits to close a given contactat the distant'station accordingto its position in the sequence of impulses, and means for rotating the commutator to transmit the impulses in a predetermined sequence.

, 16. In a transmitter the combination of a keyboard mechanism comprising means for simultaneously closing a break in a plu rality of circuits, a commutator for com pletely closing said circuits selectively to transmit impulses in .a predetermined se-' quence to a distant station, 'a -magnct and means actuated thereby to effect the rotation of the commutator, a normally open circuit in which saidmagnet is included,- means for closing said last-named circuit when a key lever depressed, an auxiliary circuit in which said magnet is also included, and means on the commutator for closing said lever inits depressedposit ionav auxiliary circuit after the rotation of the commutator has begun and for opening the same and also. said normally open circuit after the-impulses have been transmitted.

17. In a'transmitter the combination of v a keyboard mechanism comprising key levers and selector bars adapted to be moved t-hereby, circuits having normally open contacts adaptedto be closed bysaid bars, a I locking magnet included ina normally open 7 5 circuit,n1eans for closing lZllGCll'CLllt of said,

magnet when any one ofthezkey levers is depressed, andmeans actuatedby said magnet when energized'to looka given key 18. In a transmitter the combination of'a keyboard mechanism comprlsin a unlversal bar adapted to be moved/by a of the key vlevers, a commutator, a'mag'net and means' connected therewith to effect the rotation of said commutator, a normally open circuit adapted to be closed by said universal bar and inwhich .said ma et is included, a locking magnet the circuit of which'is closed through said commutator, and mechanism actuated by said locking magneti when energized to maintain 'a given key lever depressed until the impulses have been transmitted.

19. In a transmitter thec oinbination of a -keyboard' mechanism comprising selector bars and a universal bar, keylevers to effect the movement of said bars, circuits having normally open contacts adapted tobe closed by said selector bars, a commutator for [completely closing the circuits a break in which was closed by the selector bars, a magnetand means connected therewith to rotatesaid commutator, a normally open circuit in which said magnet is included and which is adapted to be, completely closed by said universal bar when any one of the key-leversis depressed, a :locking magnet the circuit of which is closed through said commutator, andmechanisin actuated by said locking magnet to anaintain a given key lever depressed until the iinpulses have been transmitted.

20. In a ll ansmit'ter, the combination'of a keyboard mechanism comprising means for simultaneously closing contacts in a plurality of circuits, a commutator for completely closing said circuits selectively to transmit impulses in a predetermined se-' quence to a distant station, means for rotating said commutator, a locking magnet and means actuated thereby to maintain said contacts closed untilthe impulses have been transmitted, andmeans actuated by the keys ofthe key-board when depressedfto close the circuit of said magne 21. In a tra-nsmitter, the combination of key-levers, a series of selector bars arranged transversely of and adapted to be moved by said key-levers in two directions, and circuits having. normally open contacts adapted to be closed by said bars when moved in either direction.

In a transmitter, the combination of key-levers, a series of selector bars arranged trai'lsvei'sely of said key-levers, said bars having notches with inclined side walls so disposed relatively to the key-levers as to be moved longitudinally in either direction when a key-lever is lepressed to strike an inclined wall, and circuits havingnormally open contacts adapted to be closed by said when moved in either direction.

In a transmitter, the combination of a keyboard mechanism comprising means for closing contacts in a plurality of circuits, a commutator for completely closing said circuits selectively to transmit impulses in a predetermined sequence to a distant station, a magnet and means actuated thereby to rotate the commutator, means for closing the circuit of said ma net when a key is depressed, and means or maintaining the circuit closed until the commutator has made a complete revolution.

21L. In a transmitter, the combination of key levers, selector bars adapted to be moved by said levers in two directions and so disposed that the same number of said bars will be moved simultaneously by any one of said levers, circuits having normally open contacts adapted to be closed by said bars moved in either direction, and means for ccnnletel 1 closin the selected circuits in a predetermined sequence for transmitting impulses to a distant station.

25. In a transmitter, the combination of key levers, selector bars adapted to be moved by said levers longitudinally in either direction and so disposed that the same number of bars will be moved simultaneously by any one of said levers, circuits having norinallyopeir contacts adapted to be closed by said bars when moved in either direction, and means for completely closing the selected circuits in a predetermined sequence for transmitting impulses to a distant station.

26. In a transmitter, the combination of key levers, selector bars adapted to be moved longitudinally in either direction by said levers, circuits having normally open contacts, two batteries included in said circuits, each selector bar being adapted to close a contact in terminals of opposite polarity when moved by a corresponding key lever, and means for completely closing selected circuits in a predetermined sequence for transmitting impulses to a distant station.

In testimony whereof I have hereunto signed my name in the presence of two subscribing witnesses. I

. GEORGE A. CARDWVELL. Witnesses I K. G. Ln Ann, G. V. GILMORE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0.? 

